Over the past few years, many regulations have appeared, among which mention may be made of the following regulations:                WEEE—Waste Electrical and Electronic Equipment-2002        ROHS—Restriction of the use of certain Hazardous Substances-2002        End-of-Life Vehicle Recycling—ELV Recycling-2002        REACH—Registration, Evaluation and Authorization of Chemicals-2007        GHS—Globally Harmonized System of Classification and Labelling of Chemicals-2005.        
Thus, by virtue of their ecotoxicity, the use of zinc containing pigment compounds has become more and more complex over the years.
This is notably the case of zinc phosphate and zinc oxide.
The classification of zinc salts, including notably zinc phosphate and zinc oxide, was thus established in 2004. Zinc phosphate is particularly mentioned in the 28th A.T.P.—Adaptation to Technical Progress—of European directive 67/548/EEC. Zinc phosphate is labeled N/dangerous for the aquatic environment, and R50/53—“Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment”.
Table 1 recapitulates, according to the amounts of zinc phosphate Zn3(PO4)2, 2 to 4H2O that are used in a product, the labeling restriction and also the associated working code risk phrases in accordance with directive 99/45/EC.
TABLE 1Labeling and risk phrases for zinc phosphateuse in a product according to 1999/45/EC.Quantity ofZn3(PO4)2LabelingRisk phrase>25%R50/53Very toxic to aquatic organisms,may cause long-term adverse effects inthe aquatic environment2.5%-25%R51/53Toxic to aquatic organisms, maycause long-term adverse effects in theaquatic environment0.25%-2.5% NoneR52/53Harmful to aquatic organisms, maycause long-term adverse effects in theaquatic environment.<0.25%  NoneNone
Thus, any formulation which contains more than 2.5% by weight of this compound is consequently labeled N/Dangerous for the aquatic environment. A new need has thus emerged since certain markets do not accept this labeling and require pigment and compounds which do not lead to the N labeling.
In accordance with directive 99/45/EC, the formulator, in order to avoid the N labeling, is restricted to the use of less than 2.5% by weight of a product N, R50/53 such as zinc phosphate; however, in the case of anti-corrosion paints and coatings, resistance effectiveness increases with the zinc phosphate content.
It should be noted that, conventionally, according to European directive 1999/45/EC, the term “substances” defines chemical elements and their compounds in the natural state or as obtained by any method of production, including any additive necessary for preserving the stability of the product and any impurity deriving from the method, but with the exclusion of any solvent which can be separated without affecting the stability of the substance or modifying its composition.
It should also be noted that, conventionally, the term “preparations” defines mixtures or solutions composed of two substances or more.
In this context, Zinc free pigment and compounds used in anti-corrosion paints, which had been developed over the past few years, are of renewed interest. Patents have notably been filed on β-tricalcium phosphate (Budenheim, 1991, DE 4014523 A1), and on mixtures of β-tricalcium or dicalcium phosphate and trimagnesium phosphate (Budenheim, 1996-1997, DE 195 41 895 A1-U.S. Pat. No. 5,665,149A).
It has also been demonstrated that anti-corrosion pigments containing magnesium phosphate have an advantageous appeal in paint (Albright and Wilson, 1976, U.S. Pat. No. 3,960,611A), without however equaling zinc phosphate.
These zinc-free pigments are effective in certain paint systems but are not as universal as zinc phosphate. Indeed, zinc phosphate is effective in most of the formulations used in anti-corrosion paint.